Reduce custom utilities for arrays/bytes

[adamhathcock]

Trust the framework

[Copilot]

Pull Request Overview

This PR refactors the utility library by removing custom implementations in favor of framework-provided functionality. The changes reduce maintenance burden and leverage well-tested platform APIs, particularly for stream operations and array handling.

Key changes include:

• Replacing custom TransferTo with framework's CopyTo for stream operations
• Using Buffer.BlockCopy instead of custom array copy wrapper
• Consolidating namespace structure by removing the Helpers namespace
• Adding comprehensive unit tests for existing utility methods

Reviewed Changes

Copilot reviewed 24 out of 24 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/SharpCompress.Test/UtilityTests.cs	Adds comprehensive test coverage for utility methods including URShift, ReadFully, Skip, date conversions, and other helper functions
tests/SharpCompress.Test/TestBase.cs	Removes global using directive for Helpers namespace
tests/SharpCompress.Test/Tar/TarReaderTests.cs	Replaces TransferTo with standard CopyTo
tests/SharpCompress.Test/Rar/RarReaderTests.cs	Replaces TransferTo with standard CopyTo
src/SharpCompress/Writers/Zip/ZipWriter.cs	Replaces TransferTo with standard CopyTo
src/SharpCompress/Writers/GZip/GZipWriter.cs	Replaces TransferTo with standard CopyTo
src/SharpCompress/Utility.cs	Removes custom array copy, TransferTo overloads, Find, CheckNotNull methods; refactors Skip methods; adds NET60_OR_GREATER conditional compilation for ReadFully
src/SharpCompress/Readers/Zip/ZipReader.cs	Updates CheckNotNull to NotNull
src/SharpCompress/Readers/Tar/TarReader.cs	Updates CheckNotNull to NotNull
src/SharpCompress/Readers/ReaderFactory.cs	Updates CheckNotNullOrEmpty to NotNullOrEmpty and CheckNotNull to NotNull
src/SharpCompress/Readers/Rar/RarReader.cs	Updates CheckNotNullOrEmpty to NotNullOrEmpty and CheckNotNull to NotNull
src/SharpCompress/Readers/GZip/GZipReader.cs	Updates CheckNotNull to NotNull
src/SharpCompress/Readers/Arc/ArcReader.cs	Updates CheckNotNull to NotNull
src/SharpCompress/NotNullExtensions.cs	Adds NotNullOrEmpty method and updates Empty methods to use collection expression syntax
src/SharpCompress/LazyReadOnlyCollection.cs	Updates namespace from Helpers to SharpCompress
src/SharpCompress/Factories/Factory.cs	Updates CheckNotNull to NotNull
src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.unpack50_cpp.cs	Replaces custom Copy with Buffer.BlockCopy
src/SharpCompress/Archives/Zip/ZipArchive.cs	Updates CheckNotNullOrEmpty to NotNull and CheckNotNull to NotNull
src/SharpCompress/Archives/Tar/TarArchive.cs	Updates CheckNotNullOrEmpty to NotNullOrEmpty and CheckNotNull to NotNull; replaces TransferTo with CopyTo
src/SharpCompress/Archives/SevenZip/SevenZipArchive.cs	Updates CheckNotNullOrEmpty to NotNullOrEmpty and CheckNotNull to NotNull
src/SharpCompress/Archives/Rar/RarArchive.cs	Updates CheckNotNullOrEmpty to NotNullOrEmpty and CheckNotNull to NotNull
src/SharpCompress/Archives/IArchiveEntryExtensions.cs	Replaces TransferTo with standard CopyTo
src/SharpCompress/Archives/GZip/GZipArchive.cs	Updates CheckNotNullOrEmpty to NotNullOrEmpty and CheckNotNull to NotNull
src/SharpCompress/Archives/ArchiveFactory.cs	Updates CheckNotNullOrEmpty to NotNullOrEmpty and CheckNotNull to NotNull

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[Copilot]

Pull Request Overview

Copilot reviewed 24 out of 24 changed files in this pull request and generated no new comments.

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